Abstract: To explore the effects of different Agrobacterium tumefaciens strains and their time and concentration on the transient expression of foreign genes based on geminivirus expression vectors, three common A. tumefaciens strains and replicative plant expression vectors based on the bean yellow dwarf virus (BeYDV) were used as experimental materials. JP+1The exogenous green fluorescent protein (GFP) gene was introduced into Nicotiana benthamiana L. leaves to achieve transient expression by transient transformation mediated by A. tumefaciens. The effects of different A. tumefaciens strains, concentration, and time on transient expression were compared. Results showed significant differences among the three different strains of A. tumefaciens in the transient expression of GFP in N. benthamiana leaves. Among them, the transformation efficiency of strain EHA105 was the highest, followed by LBA4404, and then GV3101. In addition, the optimum concentrations of GV3101, EHA105, and LBA4404 were 0.5, 0.3, and 0.3, respectively, and the best time was 4 d. These results suggest that the differences in chromosome structure and Ti plasmid of the A. tumefaciens strains are important factors affecting the concentration of A. tumefaciens and the instantaneous expression efficiency of foreign genes during transient transformation.